Minute/small in seemingly expansive range (6)
I believe the answer is:
massif
'range' is the definition.
(I've seen this before)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for massif that I've seen before include "Extensive raised area" , "series of peaks" , "huge piece of crust" , "Compact group of mountains" , "Mountainous block" .)